Quick answer: One cubic yard of mulch covers about 100 sq ft at 3 inches deep; a 2-cu-ft bag covers ~8 sq ft. Multiply bed area × depth and divide by 324 for cubic yards at 1-in depth.
Calculate cubic yards or bags of mulch for garden beds, tree rings, and landscaping. Includes bulk vs bag cost comparison.
Landscaping supply yards sell mulch and soil by the cubic yard. Big box stores sell it by the bag. Which is cheaper?
The most common mistake homeowners make is piling mulch high against the trunk of a tree, creating a "volcano" shape. This kills trees.
Why? Mulch holds moisture. If it touches the tree bark, the bark stays constantly wet, leading to rot, fungal diseases, and inviting rodents to chew the bark in winter. It also encourages roots to grow up into the mulch and "girdle" the trunk, strangling the tree.
More is not always better. Too much mulch can suffocate roots and prevent water from reaching the soil.
Landscaping projects come in all shapes. Here is how to use our calculator for the most common scenarios.
It depends on the moisture content. Hardwood mulch typically weighs between 400 and 800 pounds per cubic yard. Pine bark is lighter (around 400 lbs), while double-shredded hardwood holds water and can weigh nearly a ton.
For flower beds, no. Fabric prevents mulch from breaking down into the soil, and weeds will eventually grow on top of the fabric in the decomposing mulch layer. For gravel pathways or rock beds, yes, fabric is essential to prevent mixing with the dirt.
Hardwood mulch typically breaks down and fades in 1-2 years. Pine bark nuggets last 3-5 years because they are denser. Rubber mulch is permanent but doesn't improve soil health.
Yes, but only in thin layers (1 inch) and let them dry first. If you pile wet grass clippings thick, they will mat together, smell like rotting ammonia, and generate enough heat to burn plant roots.
Straw (not hay, which has seeds) is excellent because it reflects heat and keeps veggies clean. Untreated grass clippings or shredded leaves are also great because they add nitrogen to the soil as they decompose.
There are 27 cubic feet in 1 cubic yard (3 ft × 3 ft × 3 ft). If a bag holds 2 cubic feet, you need 13.5 bags to equal one cubic yard; if it holds 3 cubic feet, you need 9 bags. Our calculator does this conversion for you automatically — just enter your area and depth above.
Every constant this calculator uses and where it comes from, so you can check it rather than take our word for it.
Local codes amend the model IRC and adopt different cycles — your building department governs. Manufacturers revise yields; where your product's data sheet disagrees with a default here, use the product's number. See our full methodology.